Fixed bugs in issue

src/main/java/dotsandboxes/DotsAndBoxesGrid.java

 package dotsandboxes;
 
-
 import java.util.ArrayList;
 import java.util.Arrays;
 import java.util.function.Consumer;
@@ -25,11 +24,13 @@ import java.util.function.Consumer;
  * - for each column, there are as many horizontals as there are corner dots.
  * - for each column, there is one less box than the number of corner dots
  *
- * For example, in this (4, 3) grid, there are (3, 3) horizontal lines, and (4, 2) vertical lines, and (3, 2) boxes.
+ * For example, in this (4, 3) grid, there are (3, 3) horizontal lines, and (4,
+ * 2) vertical lines, and (3, 2) boxes.
  *
  * We number all lines and boxes by their top-left coordinate.
  *
- * In Java 14+, we might use a Record class for this, but we're using 11+ as an LTS version, so we don't have that yet.
+ * In Java 14+, we might use a Record class for this, but we're using 11+ as an
+ * LTS version, so we don't have that yet.
  */
 public class DotsAndBoxesGrid {
 
@@ -50,6 +51,7 @@ public class DotsAndBoxesGrid {
 
     final int players;
     private int player = 1;
+
     public int getPlayer() {
         return player;
     }
@@ -98,9 +100,9 @@ public class DotsAndBoxesGrid {
         return boxOwners[x][y];
     }
 
-
     /**
      * Checks whether a box has been fully drawn (all four sides)
+     * 
      * @param x coordinate of the left side of the box
      * @param y coordinate of the top of the box
      * @return true if all four sides have been drawn.
@@ -109,13 +111,17 @@ public class DotsAndBoxesGrid {
         if (x >= width - 1 || x < 0 || y >= height - 1 || y < 0) {
             return false;
         }
-
-        // A box is complete if the north and south horizontals and the east and west verticals have all been drawn.
+        // A box is complete if the north and south horizontals and the east and west
+        // verticals have all been drawn.
         // FIXME: You'll need to fix this code (after writing a test first).
-        return true;
+        return (getHorizontal(x, y) && getHorizontal(x, y + 1) && getVertical(x, y) && getVertical(x + 1, y));
+
     }
 
-    /** Tries to claim a box for a player. If the box is complete, sets the ownership and returns true. */
+    /**
+     * Tries to claim a box for a player. If the box is complete, sets the ownership
+     * and returns true.
+     */
     private boolean claimBox(int x, int y, int p) {
         if (boxComplete(x, y)) {
             boxOwners[x][y] = player;
@@ -126,25 +132,32 @@ public class DotsAndBoxesGrid {
     }
 
     /**
-     * "Draws" a horizontal line, from grid point (x, y) to (x + 1, y). (i.e. sets that line to true)
+     * "Draws" a horizontal line, from grid point (x, y) to (x + 1, y). (i.e. sets
+     * that line to true)
+     * 
      * @param x
      * @param y
      * @return true if it completes a box
      */
     public boolean drawHorizontal(int x, int y, int player) {
         if (x >= width - 1 || x < 0) {
-            throw new IndexOutOfBoundsException(String.format("x was %d, which is out of range. Range is 0 to %d", x, width - 1));
+            throw new IndexOutOfBoundsException(
+                    String.format("x was %d, which is out of range. Range is 0 to %d", x, width - 1));
         }
         if (y >= height || y < 0) {
-            throw new IndexOutOfBoundsException(String.format("y was %d, which is out of range. Range is 0 to %d", y, height));
+            throw new IndexOutOfBoundsException(
+                    String.format("y was %d, which is out of range. Range is 0 to %d", y, height));
         }
 
         // FIXME: You need to throw an exception if the line was already drawn.
+        if (getHorizontal(x, y)) {
+            throw new IllegalStateException("This line has already been drawn!");
+        }
 
         this.horizontals[x][y] = true;
 
         // Try to claim the north or south boxes
-        boolean claimN = claimBox(x, y-1, player);
+        boolean claimN = claimBox(x, y - 1, player);
         boolean claimS = claimBox(x, y, player);
         if (claimN || claimS) {
             notifyObservers();
@@ -157,25 +170,32 @@ public class DotsAndBoxesGrid {
     }
 
     /**
-     * "Draws" a vertical line, from grid point (x, y) to (x, y + 1). (i.e. sets that line to true)
+     * "Draws" a vertical line, from grid point (x, y) to (x, y + 1). (i.e. sets
+     * that line to true)
+     * 
      * @param x
      * @param y
      * @return true if it completes a box
      */
     public boolean drawVertical(int x, int y, int player) {
         if (x >= width || x < 0) {
-            throw new IndexOutOfBoundsException(String.format("x was %d, which is out of range. Range is 0 to %d", x, width));
+            throw new IndexOutOfBoundsException(
+                    String.format("x was %d, which is out of range. Range is 0 to %d", x, width));
         }
         if (y >= height - 1 || y < 0) {
-            throw new IndexOutOfBoundsException(String.format("y was %d, which is out of range. Range is 0 to %d", y, height - 1));
+            throw new IndexOutOfBoundsException(
+                    String.format("y was %d, which is out of range. Range is 0 to %d", y, height - 1));
         }
 
         // You need to throw an exception if the line was already drawn.
+        if (getVertical(x, y)) {
+            throw new IllegalStateException("This line has already been drawn!");
+        }
 
         this.verticals[x][y] = true;
         // Try to claim the north or south boxes
         boolean claimE = claimBox(x, y, player);
-        boolean claimW = claimBox(x-1, y, player);
+        boolean claimW = claimBox(x - 1, y, player);
         if (claimE || claimW) {
             notifyObservers();
             return true;
@@ -188,10 +208,11 @@ public class DotsAndBoxesGrid {
     }
 
     public boolean gameComplete() {
-        // Students who took COSC250 might recognise this style of code. This is Java's version of higher order functions.
-        // The grid is complete if "for all rows, all the boxes in that row have a non-zero owner"
+        // Students who took COSC250 might recognise this style of code. This is Java's
+        // version of higher order functions.
+        // The grid is complete if "for all rows, all the boxes in that row have a
+        // non-zero owner"
         return Arrays.stream(boxOwners).allMatch((row) -> Arrays.stream(row).allMatch((owner) -> owner > 0));
     }
 
-
 }